Railway bosses have criticised union leaders for rejecting what they claim is a ‘significant pay offer’.

Govia Thameslink Railway (GTR) said its offer to ASLEF’s Southern Railway and Gatwick Express drivers would, over four years, take their base salary to £60,683.

But the union will ballot members on the next steps, which could involve further strike action.

The ballot commences on June 29 and closes at 10am on July 13. GTR claims potential industrial action could fall in school holiday time.

A GTR spokesman said: “People will be amazed the ASLEF leadership has rejected such a significant pay offer for their members, especially as they have twice before accepted the extension of driver-controlled operation which has now been in place for over six months.

“ASLEF should now suspend the overtime ban due to start on June 29, pending the result of this new ballot, because we won’t be able keep our pay offer on the table if they press ahead with interim industrial action.

“This ballot is a real chance for drivers to end this dispute by showing they want to accept the 23.8% pay offer and work with us to modernise the congested Southern network as updated infrastructure, trains and working practices provide the service passengers need and deserve.”